Genetic Tests, Health Screenings May Identify Individuals at Risk of Premature Heart Disease

When both the clinical criteria and genetic testing were combined, 6.6 familial hypercholesterolemia cases per 1000 individuals screened were found.

Genetic tests and health screenings may help identify more than 1 million adults in the United States who carry a gene for familial hypercholesterolemia, which is a common genetic disorder that causes elevated low-density lipoprotein (LDL) cholesterol, according to the results of a study published in the Journal of the American Heart Association.

“Currently, most individuals aren’t diagnosed with familial hypercholesterolemia until they are in their 50s. If a young adult is identified to have familial hypercholesterolemia, they would likely benefit from earlier and more aggressive treatment to prevent heart attack and stroke,” Brandon Bellows, PharmD, MS, an assistant professor of medical sciences at Columbia University in New York City, said in a statement.

The American Heart Association recommends that all individuals aged 20 years or older have their cholesterol and other heart risk factors checked every 4 to 6 years, if the risk remains low.

Familial hypercholesterolemia screening is not standard and requires that accurate collection of additional clinical information or diagnostic genetic testing, but genetic testing may not be affordable for individuals when it is not covered by insurance.

In the study, investigators aimed to determine how many individuals with familial hypercholesterolemia could be identified if they were screened using clinical factors, including cholesterol levels and the presence of early heart disease for them or close family members, with and without genetic testing.

The investigators gathered clinical information and genetic test results for approximately 50,000 individuals, aged 40 to 69 years old, from the United Kingdom Biobank between 2006 and 2010. They estimated the probability each individual had of carrying the generic variant based on their clinical information. Additionally, they applied the relationships observed in the database to a dataset of almost 40,000 individuals, aged 20 years or older, from the National Health and Nutrition Examination Survey to estimate familial hypercholesterolemia genetic variants in the US population who did not have genetic test results.

To evaluate the performance of clinical criteria in the US data, the investigators used the Dutch Lipid Clinic Network criteria to classify individuals with definite or probable familial hypercholesterolemia based on a scoring system that combined a personal history of early heart disease; family history of early heart attack or heart-related angina in a sibling, parent, or child; and high undertreated LDL cholesterol levels with more points for higher cholesterol levels.

The results of the study showed that the clinical criteria alone identified 3.7 familial hypercholesterolemia cases per 1000 individuals screened, and genetic testing alone identified 3.8 familial hypercholesterolemia cases per 1000 individuals screened.

When both the clinical criteria and genetic testing were combined, 6.6 familial hypercholesterolemia cases per 1000 individuals screened were identified.

Furthermore, in adults aged 20 to 39 years old, the clinical criteria alone identified 1.3 familial hypercholesterolemia cases per 1000 individuals screened and rose to 4.2 when genetic testing was included.

“Screening for familial hypercholesterolemia should include clinical factors and genetic testing. Individuals with high cholesterol levels or with a family member that had a heart attack at a young age should undergo genetic testing for familial hypercholesterolemia,” Bellow said.

“Early diagnosis and treatment of familial hypercholesterolemia are the best ways to reduce the risk of early heart attack or stroke,” he said.

Reference

Health screening, genetic tests might identify people at risk of premature heart disease. EurekAlert. News release. May 18, 2022. Accessed May 20, 2022. https://www.eurekalert.org/news-releases/952718